Printing mechanism



Jan. 19, 1943. F. J. MAUS ETAL PRINTING MECHANISM 2 Sheets-Sheet 1 Filed May .16, 1939 ENTORS MAUS .NUXOLL BY W/ ATTORNEY FIG. 4

Jan. 19, 1943. 2,308,563

F. J. MAUS ET AL PRINTING MECHANISM Filed May 16, 1939 2 Sheets-Sheet '2 r IIII/IJ.

III/II Patented Jam 19, 1943 UNITED STATES PATENT OFFICE PRINTING MECHANISM Application May 16, 1939, Serial No. 273,842

Claims. (Cl. 197-125) This invention relates primarily to telegraph receivers and more particularly to that type of telegraph receivers wherein type bars are selectively actuated in accordance with received telegraph signals to print on a recording tape or web.

Type bar telegraph receivers are generally divided into two principal types, namely, page printers and tape printers. The page printers, as the name implies, record characters representative of the received signals in successive lines on a page or web of substantial width which is advanced or line fed after each line of print, whereas a tape printer records the signal on a comparatively narrow tape, one character appearing in each transfer section of the tape and the tape being advanced concomitantly with each recording operation. Generally by making the necessary provisions such as for example, transmitting certain printer function signals, such as line feed and carriage return signals, where these functions are not performed automatically, a page printer may be employed in place of a tape printer. Similarly, a tape printer may be substituted or employed in place of a page printer. However, for certain types of services, one type of printer is to be preferred over the other. Heretofore when it was desired to substitute one type of printer for the other, the complete printer had to be changed as ach type was constructed differently.

In accordance with the above, one of the primary objects of the invention is to provide an attachment which replaces some of the elements of a page printer, such as that disclosed in a copending application of Noxon et al., Ser. No. 66,906, filed March 3, 1936, issued February 11, 1941, Patent No. 2,231,215, which will convert such page printers into tape printers.

Another object of the invention is to provide a device of the above type which may be cheaply manufactured, efficient and quiet in operation and easily attached to printers of the above type. In type bar printers, whether of the page or tape type, the printing is usually effected by the type bars pressing an inking ribbon onto the recording paper which is supported by a platen. In a page printer the platen extends the full width of the paper and obviously there is less wear thereof per unit of area'for a given number of printing operations on a page printer platen than on the smaller platen employed in a tape printer, the platen in a tape printer being usually little wider than the tape. In a tape printer the tape is usually supported by the small platen and the platen rotated or stepped a predetermined amount, to cause advancement of the tape through the printer on each printing operation. The tape employed in tape printers is oftentimes gummed on the back so that it may be gummed down on a blank to form a message of the regular size and in humid weather considerable diificulty is encountered by the gum on the back of the paper softening and causing the paper to stick to the resilient platen. While this trouble is obviously more likely to occur when the printer has been idle for a time, it may occur during the operation thereof. Another difficulty usually encountered in a tape printer is that with a small platen the type bars strike in the same spot comparatively frequently and soon wear the platen or cause it to become pitted resulting in uneven or poor printing.

In view of the above another object of the invention is to provide an attachment for printers of the above type whereby they may be converted to tape printers and wherein the recording tape is only in contact with the platen for a very short time or only during the actual printing upon the tape.

Another object is to provide a platen which rotates at right angles to the direction of movement of the recording tape and slowly moves back and forth along the axis thereof so that a large number of printing operations may be performed before a type bar strikes the platen in exactly the same spot.

Another object of the invention is to provide a tape printer wherein the tape is completely visible at all times even up to the last printed character and all within the normal line of vision.

These and other objects of the invention will be more apparent when taken in conjunction with the following detailed description and drawings,

' in the latter of which:

Fig. 1 is a left hand elevational view of a printer of the above type wherein the attachment for converting it into a tape printer is shown replacing the regular platen carriage Fig. 2 is a plan view of the platen and the actuating mechanism therefor together with the tape feeding mechanism;

Fig. 3 is a vertical sectional view taken substantially through the transfer center of the recorder;

Fig. 4 is a fragmentary sectional view taken substantially on line 4-4 of Fig. 2;

Fig. 5 is a plan view of the platen and the actuating mechanism therefor showing the limits of axial movements thereof; and

Fig. 6 is a fragmentary sectional view taken substantially on line 6-8 of Fig. 2.

For a detailed description of the elements of the page printer reference may be had to the above mentioned copending application, and hereinafter the description of the elements and operation thereof will be limited and only those described as will be necessary for a ready understanding of the present invention.

Referring first to Fig. 3, the selector mechanism of the printer employs a plurality of horizontal permutation bars II arranged in superimposed relation that are selectively positionable in the well known manner into one or the other of two positions in response to received signals. The permutation bars II have arranged on their front or left hand side as shown in Fig. 3 a series of notches, the notches in each bar being arranged differently from those in the others. For each combination of settings of the permutation bars H, a notch in each of the bars is in vertical alignment with a notch in each of the other bars and following the setting-thereof a group of drop-in bars I2 are allowed to approach the notched sides of the permutation bars whereupon the one opposite the aligned row of notches is allowed to enter therein and in so doing pivot a slight amount further than the rest. A bail member l3 controls the operation of the drop-in bars l2 in timed relation with the selective positioning of the permutation bars Associated with the upper end of each one of the drop-in bars I2 is a depending hook l4 and when a dropin bar I2 is selected by entering a row of aligned notches in the permutation bars II, it causes the shoulder l6 of the associated hook H to move heneath a bail member ll. The ball hereinafter referred to as the print or operating bail pivots about a rod l8 and is controlled by a cam l9 operating in timed relation with the movement of the drop-in bars l2. The cam l8 makes one revolution in conjunction with each received code combination and in so doing allows the ball I! to move downward, whereupon it engages the selected one of the hooks l4. The hooks H are pivotally attached adjacent the ends of associated type bar operating levers such as 2| and function control levers such as 22. The type bar operating levers 2| are pivoted adjacent their right hand ends at a member 23 forming a transverse support in the printer and when one of the hooks l4 associated with a type bar operating lever is moved in a downward direction a pin 24 in the lever 2| pivots an associated bell crank 23 in a counterclockwise direction. An arm of each of the hell cranks 26 has articulated thereto one end of a link 21, the other end of which engages an associated type bar 28. The type bars are pivotally mounted at 29 and when the front end of their associated type bar operating levers 2| moves downward, the described linkages cause the type bar to move upward to perform a recording operation as will hereinafter be described.

In the above mentioned page printer the platen carriage is movable to and fro to effect letter spacing and return of the carriage for the beginning of new lines of print. Theplaten carriage is carried in a cradle indicated in general by reference numeral 3|, Figs. 1 and 3, which as hereinafter described is movable up and down within predetermined limits so that either one or the other of the type elements 32 and 33 on a type bar 28 will be recorded when a type bar is actu-' ated. The platen carriage cradle 3| is attached to the forward or right hand ends as shown in Fig. 1 of levers 34 and 35, the left hand ends of which are pivoted at 38 and 31 in the printer frame structure. The pivots of the levers 34 and 35 are in substantially parallel planes and permit movement of the platen carriage 3| in substantially a straight line. With the cradle 3| in its lower position the selection of the hook l4 in response to a shift signal associated with the function lever 22 causes the cradle to he raised to its up position. The lever 22 is pivoted at 38, Fig. 3, and during its operation the right hand and engages a member 39 in the cradle 3| to raise the same. The cradle 3| is latched in its upper position by a latch member 4|, Fig. l, engaging a pin 42 in the lever 35. When it is desired to lower necessary to convert the above mentioned page printer into a tape printer is to remove the platen carriage and replace it with a plate 44 upon which is mounted the tape platen indicated generally by reference numeral 45 and the tape actuating mechanisms hereinafter described. The plate 44 has attached to the underside thereof brackets 46, Fig. 3, which are attached by screws 41 to a member 48 of the carriage cradle 3|. The front of the plate 44 is attached to a rail member 49 of the cradle by screws 5|, spacers 52 on the screws 5| spacing the plate the proper'distance from the rail 49.

The above mentioned platen 45 is freely mounted on a shaft 53, which is disposed in a horizontal position with the axis thereof extending transversely of the machine. The complete platen 45 is composed of a ring of resilient material 54, such as rubber, mounted on a platen hub 56. The hub 55, as shown in Figs. 3 and 4, has formed therein a keyway which engages a key 51 on the platen shaft 53. In this manner the platen 45 is movable axially along the shaft 53, but is at all times rotatable therewith. The platen shaft 53 is pivotally mounted in brackets 58 attached to the plate 44 and collars 59 on the shaft prevent longitudinal movement thereof. Fixed to the left hand and of the platen shaft 53 for rotation therewith is a bevel gear" 6| which serves to rotate the platen in a manner hereinafter described.

As fully described in the aforementioned copending application, each time a recording or a word space operation is performed the pinion 62, Figs. 1, 2 and 3, is rotated apredetermined amount to effect movement of the platen carriage in a letter spacing direction. As hereinafter described when the machine is employed as a tape printer the pinion 62 through various other gears serves to move the platen 45 and advance the recording tape 65. A bracket 63 is attached by screws 64 to the back edge of the plate 44':and pivotally supports a second pinion 66. The second pinion 66 is of substantial'length so that as the cradle 3| is moved up to its shift position as indicated by the dot-dash outline thereof in Fig. 3, the pinion 66 will still remain in engagement with the pinion 62. The pinion 66 in turn meshes with a gear 61 pivotally mounted on a shoulder screw 68 in the plate 44 which also meshes with another gear 69. The gear 69 is fixed for rotation therewith to a bevel gear 10 which is pivoted on a shoulder screw supported in the plate 44. The gear Ill meshes with the gear in on the platen shaft in and through the described gear train: each time the pinion 82 rotates or steps the platen shaft 58 also rotates or steps a predetermined amount. The gear 88 also meshes with and drives another gear 12. Fig. 2, to which is fixed for rotation therewith a knurled tape advancing or feed roller 18 which is pivotally supported on a stud 14, best shown in Fig. 6, extending from the plate 44. Also meshing with the gear 12 is another gear 18, Figs. 2 and 6, which is pinned for rotation therewith to a, pressure roller 11. The pressure roller 11 and gear 18 are forced on a pin 18 which is carried in the free ends of pivoted levers 18. The

levers 18 are pivoted on a shoulder screw 8|, Fig. 2, and a spring 82 attached thereto keeps the gears 12 and 18 in mesh and the pressure roller 11 against the knurled feed roller 18. The recording tape 85 passes between the feed roller 18 and the pressure roller 11 so that as these rollers rotate the tape is advanced. As both the pressure roller 11 and feed roller 18 are positively driven, the slippage between the peripheries and the tape 85 is reduced to a minimum. The direction of rotation of the feedand pressure rollers 18 and 11 respectively, is such that the tape 65 is advanced from right to left as is the usual practice and during the advancement thereof it is pulled from a supply reel, not shown, at the rear of the printer, past the printing platen 45. The center portions of the pressure and the feed rollers are recessed so that the center portion of the tape does not come in contact therewith thus asoaoea preventing smudging of the printed matter thereat. Two channel shaped members 88 and 81 are located one each side of the platen 45 to guide the tape past the platen, they being so positioned that the tape 85 is normally a slight amount in front of the platen 45. The channel shaped members 88 and 81 are supported from the plate 44 by brackets such as 88 and the fronts are open so as to permit the printed matter on the center of the tape to be read and to facilitate easy threading of the tape through the printer.

As described in the above mentioned copending application the type bars 28 perform the printing. operation through an inking ribbon 88. The ribbon 88 is supplied from supply spools 8|, Fig. l, and passes through a shuttle or ribbon guide 82, Figs. 2 and .5, located in front of the platen 45. The shuttle 82 is normally below the recording tape 84 and only during each printing operation the shuttle raises the inking ribbon to the height of the recording tape, thus giving complete visibility of the characters recorded at all times. During 'a printing operation a type bar 28 presses the inking ribbon 88 and the tape 85 against the periphery of the platen 45 to leave an imprint of the type bar on the tape and as the tape advancing operation occurs followi g the printing operation, the tape is withdraw from engagement with the platen shortly after the printing operations Thus the tape is only momentarily in contact with the platen and because of this gummed tape isv much less likely to stick to the platen than it would if in contact therewith for longer intervals. The fact that the direction of movement of the tape 85 is at right angles to the direction of rotation of the platen 45 also assists in preventing the gummed v tape from sticking to the platen.

Fixed to the feed roller 18 and rotatable therewith is a star wheel 88, Figs. 2 and 6, which cooperates with a detent roller 84 carried in the I 3 end of a flexible member 88. The flexible member 88 is. supported at its fixed end in a bracket 81 on the plate 44. The gears hereinafter described which drive the gear 12 on the feed roller 18 are of such a size that the periphery of the feed roller is rotated an amount equal to one letter space concomitantly with each printing operation. Thus the tape 84 is advanced one letter space for each printing or word space operation. eThe star wheel 88 rotatable with the feed roller 18 rotates one tooth for. each tape feed operation and the roller 84 cooperating therewith insures that the feed roller 18 rotates the same amount for each tape feed operation, holds it and eliminates any back lash or play that might be present in the gears employed to drive the same.

The gear 81 has fixed to the upper side thereof by a screw 88 a bracket member 88 which carries in an oflset portion thereof a shoulder screw MI. The bracket 88 is so positioned that the shoulder screw IN is a slight amount oif center with respect to the center of the shoulder screw 88 upon which the gear 81 is mounted. The shoulder screw I 8| engages a slot I82 in an arm of a bell crank I88 pivotally mounted on a shoulder screw I84 in a bracket I88 afilxed to'the plate by screws I81. The other arm of bell crank I88 engages a groove I88 formed on the left hand side of the platen hub 58 and as the gear 81 rotates the bell crank I88 oscillates within the limits shown by the dot-dash and full outline thereof in Fig. 5 to slide the platen back and forth along the platen shaft 58. As the gear 881s comparatively large it requires a considerable number of tape feed operations for it to make one revolution during which time the platen 45 makes one complete oscillation along its shaft 58. The beveled gears 8| and 18 serve to rotate the platen 45 a predetermined amount for each tape feed operation and thetwo movements of the type wheel occur simultaneously. Thus the platen 45 is rotated about and laterally moves along the axis simultaneously. The size of the gears emare specifically set forth in the played to rotate and axially move the platen 45 are so proportioned that several revolutions and several oscillations occur before the printing blow takes place in exactly the same spot on the periphery of the platen. Thus the small platen 45 is much less likely to become pitted and any wearing thereof occurs over a surface substantially wider than the width. of a type element on a type bar 28.

It will be obvious of course that various modifications of the invention shown and described herein may be made without departing from the spirit or essential attributes thereof and it is desired therefore that only such limitations be placed thereon as are imposed by the prior art or appended claims. What is claimed is:

1. In a printing machine, a plurality of separately operable type bars for performing recording operations in invariable position, a rotatable printing platen against which said type bars strike to perform said recording operations, means including gear means for positively rotating said platen to invariably make one revolution during a first predetermined number of printing operations, and means including gear means for positively moving said platen back and forth in an axial direction to invariably make one complete oscillation during a second predetermined number of printing operations whereby a plurality of revolutions and oscillations of said platen means operated by said gear to advance said tape predetermined amount concomitantly with each printing or word space operation, a circular platen against which said type bars strike to perform said printing operations, a second means operated by said gear to positively rotate said platen a predetermined amount for each printing or word space operation and a third means operated by said gear to positively oscillate said platen in an axial direction at a non-uniform rate relative to the rotation said gear.

3. In a printing machine, a plurality of type bars selectively operable one at a time to perform printing operations on a recording tape in an invariable vertical printing plane relative to said telegraph machine, each of said type bars having a plurality of type elements arranged along the length thereof, a rotatable printing platen against which said type bars strike to perform said printing operations, the axis of said platen being perpendicular to said vertical printing plane, means guiding said recording tape for movement through said printing plane between said platen and said type bars, means for rotating said platen and advancing said tape prede-- termined amounts concomitantly with each printin operation, means for moving said platen back and forth along the axis thereof to make one complete oscillation in a predetermined number of printing operations different from that required to rotate said platen one revolution, means for moving said platen and tape so as to change the positions thereof in said vertical printing plane to permit the printing of one of said type elements on said type bars at a time, and means for maintaining said platen rotating and axially moving means operative during the operation of said last mentioned means.

4. In a printing machine, a plurality of type bars selectively operable one at a time to perform printing operations on a recording tape in an invariable vertical printing plane relative to said machine, an inking ribbon passing throush said vertical plane normally out of the path of movement of said type bars, a rotatable printing platen in said printing plane, tape guides for supporting said tape for movement in the direction of its length in front of and out of engagement with said platen and in the path of movement of said type bars, means operative during the operation of any one of said type bars to move said inking ribbon into the path of movement thereof whereby said operated type bar presses said ribbon onto said tape and said ribbon and tape against saidplaten to eifect a recording operation, and means operative followin each recording operation to advance said tape a predetermined amount, said tape being withdrawn from engagement with said platen as an incident to said advancing operation.

5. In a printing machine, a plurality of type bars selectively operable one at a time to perform printing operations on a recording tape in an invariable vertical printing plane relative to said machine, an inking ribbon passing through said vertical plane normally out of the path of movement of said type bars, a rotatable printing platen in said printing plane, means for supporting said tape for movement in the direction of its length in front of and out of engagement with said platen and in the path of movement of said type bars, means. operative during the operation of any one of said type bars to move said inking ribbon into the path of movement thereof whereby said operated type bar presses said ribbon onto said tape and said ribbon and tape against said platen to effect a recording operation, a first positively acting means operative to pull said tape away from said platen and through said printing plane a predetermined amount following each printing operation, and a second and third positively acting means operable with said first means to rotate said platen and move the same back and forth along the axis thereof to make one revolution in a first predetermined number of printing operations and one oscillation in a second predetermined number of printing operations whereby a plurality of revolutions and oscillations of said platen occur before a printing operation takes place at the same spot on said platen.

FRANK J. MAUS. FRED G. NUXOLL. 

